Smokeless tobacco for oral use includes chewing tobacco, dry snuff and moist (wet) snuff. Generally, dry snuff has a moisture content of less than 10 wt % and moist snuff has a moisture content of above 40 wt %. Semi-dry products having between 10% to 40 wt % moisture content are also available.
Smokeless tobacco products for oral use are made from tobacco leaves, such as lamina and stem of the tobacco leaf. The material from roots and stalks are normally not utilized for production of smokeless tobacco compositions for oral use.
There are two types of tobacco-containing moist snuff, the American type and the Scandinavian type which is also called snus. American-type moist snuff is commonly produced through a fermentation process. Scandinavian-type moist snuff is commonly produced by using a heat-treatment process (pasteurization) instead of fermentation. The heat-treatment is carried out in order to degrade, destroy or denature at least a portion of the microorganisms in the tobacco preparation.
Both the American-type and the Scandinavian-type of moist snuff for oral use are available in loose form or portion-packed in a saliva-permeable, porous wrapper material forming a pouch. Pouched moist snuff, including snus, is typically used by the user by placing the pouch between the upper or lower gum and the lip or cheek and retaining it there for a limited period of time. The pouch material holds the tobacco in place while allowing saliva to pass into the interior of the pouched product and allowing flavors and nicotine to diffuse from the tobacco material into the user's mouth.
There are also oral pouched nicotine-containing non-tobacco snuff products and oral pouched nicotine-free non-tobacco snuff products available which may be offered as alternatives to oral pouched smokeless tobacco products. These oral pouched non-tobacco snuff products are generally used in the same manner as the corresponding oral pouched tobacco-containing snuff products and are herein therefore also referred to as oral pouched snuff products.
Examples of oral pouched nicotine-containing non-tobacco snuff products and the manufacture thereof are provided in WO 2012/134380.
Examples of nicotine-free non-tobacco snuff products and the manufacture thereof are provided in WO 2007/126361 and WO 2008/133563.
Oral pouched snuff products, such as oral pouched tobacco-containing snuff products and oral pouched non-tobacco snuff products, may be produced by measuring portions of the filling material (snuff composition) and inserting the portions into a nonwoven tube.
U.S. Pat. No. 4,703,765 discloses a device for packaging precise amounts of finely divided tobacco, such as snuff tobacco or the like, in a tubular packaging material into which snuff portions are injected via a fill tube. Downstream from the tube, welding means are positioned for transverse sealing of the packaging material, and also cutting means for severing the packaging material in the area of the transverse seal to thus form discrete or individual portion packages.
EP 2428450 B1 relates to a snus dosing method, wherein a portion of tobacco is filled into a dosing chamber of a dosing device and then blown out of the dosing chamber by means of blow-out air to which water vapor has been added.
Oral pouched snuff products, such as tobacco-containing snuff products and non-tobacco snuff products, may alternatively be produced by placing portions of tobacco-containing or tobacco-free moist snuff composition on a nonwoven web using a pouch packer machine in accordance with the device disclosed in U.S. Pat. No. 6,135,120. This device comprises feeding means for feeding the snuff composition into pockets formed in a rotary portioning wheel for portioning the composition into portions, at least one compression means for compressing the snuff portions, a unit for advancing a packaging material, such as a nonwoven web, in synchrony with the compressed portions, at least one discharge means for discharging the portions from the pockets to the packaging material, and a forming unit for forming individual portion packages (such as pouched smokeless tobacco products) from the discharged portions and the packaging material. At the Intended point of discharge of the portions of to the packaging material, said packaging material has the form of a tape, the compression means being arranged to compress the portions in a direction which differs from the discharging and the feeding directions. The compression is preferably effected in a direction perpendicular to the discharging and the feeding directions. The compression may be effected in the axial direction of the portioning wheel whereas the feeding and discharging may be effected in the radial direction of said wheel. This technique is herein referred to as the “NYPS” technique.
The packaging material forming the pouch in oral pouched snuff products is typically a dry-laid bonded nonwoven comprising viscose rayon fibres (i.e. regenerated cellulose) and an acrylic polymer that acts as binder in the nonwoven material and provides for heat-sealing of the pouches during manufacturing thereof. The viscose nonwoven normally used for pouched smokeless tobacco products is similar to the fabric used in tea bags. Nonwovens are fabrics that are neither woven nor knitted. Methods for the manufacturing of nonwoven materials are commonly known in the art. Further information on nonwovens is found in “Handbook of Nonwovens” by S. Russel, published by Woodhead Publ. Ltd., 2007.
The packaging material forming the pouch of the oral pouched snuff product should during manufacturing of the pouch provide for sealing, upon storage of the pouch exhibit none or a low degree of discoloration and upon usage by a consumer preserve integrity and strength, allow for a desired release profile of nicotine and flavors and provide a pleasant mouth-feel.
The organoleptic properties, such as texture, aroma, taste, shape and appearance, of the pouched snuff product, such as an oral pouched smokeless tobacco product, are of high importance to the user. It is generally desirable to provide oral pouched snuff products with rapid release of flavor and/or nicotine to provide an initial strong flavor experience and/or reduce nicotine craving.
Oral pouched snuff products are normally sized and configured to fit comfortably and discreetly in a user's mouth between the upper or lower gum and the lip. In general, oral pouched snuff products have a generally rectangular shape. Some typical shapes (length×width) of commercially available oral pouched snuff products are, for instance, 35 mm×20 mm, 34/35 mm×14 mm, 33/34 mm×18 mm, and 27/28 mm×14 mm. The thickness (“height”) of the pouched product is normally within the range of from 2 to 8 mm, such as from 5 to 7 mm. The total weight of commercially available oral pouched snuff products, such as an oral pouched smokeless tobacco product, are typically within the range from about 0.3 to about 3.5 g, such as from about 0.5 to 1.7 g, per pouched product.
The individual portioned-packed snuff products are sealed and cut apart thereby forming rectangular “pillow shaped” (or any other desired form) pouched products. Generally, each final pouched product includes parallel transverse seals at opposite ends and a longitudinal seal orthogonal to the transverse seals. The seals should be of sufficient strength to preserve the integrity of the pouched product during use while not disturbing the users experience. Heat melt-welding is commonly used today in the production of oral pouched snuff products to create the seals of the oral pouched snuff product. Heat melt-welding is generally performed by using welding apparatus heated to a temperature ranging from about 200° C. to 350° C.
U.S. Pat. No. 8,122,893 B2 discloses a machine for manufacturing pouches of a smokeless tobacco product. The machine comprises an intermittently rotatable dispensing disc with peripheral cavities, a station at which each cavity is filled with a given quantity of tobacco equivalent to a single portion, a push rod mechanism by which the portions of tobacco are ejected from each cavity of the disc at a transfer station, and a connecting duct through which the portion of tobacco ejected by the push rod from each cavity passes directly to a wrapping station where the pouches are formed, filled with the tobacco product and sealed. A rectilinear duct connects the transfer station with the wrapping station. The wrapping station comprises a tubular element positioned at the outlet end of the rectilinear duct, around which a tubular envelope of wrapping material is formed. The tubular envelope is sealed longitudinally by ultrasonic welders operating in dose proximity to the tubular element. The machine also comprises sealing means located beneath the tubular element, of which the function is to bond the tubular envelope transversely in such a manner as to form a continuous succession of pouches, each containing a relative portion of tobacco. Downstream of the transverse sealing means, the machine comprises a pair of transport belts looped around respective pulleys positioned to take up and direct the continuous succession of pouches toward cutting means by which the succession of pouches is divided up into single units.
Moreover, US 2012/0067362 A1 relates to a smokeless oral product comprising a permeable pouch of woven polylactide material which may be sealed by, for instance, a ultrasonic welding. These seams are disclosed to be smaller and more precise and therefore tidier and more visually appealing. They may also be more comfortable in the mouth of the user. Smaller seams have the further advantage that the required amount of woven material is reduced. However, apart from these advantages, ultrasonic welding and heat melt-welding are considered as equivalent welding techniques.
US 2010/059069 A1 relates to a machine for manufacturing individual bags or sachets of cohesionless material, such as pouches of snuff for oral use. The machine comprises an intermittently rotatable dispensing disc with peripheral cavities, a station at which each cavity is filled with a given quantity of tobacco equivalent to a single portion, a push rod mechanism by which the portions of tobacco are ejected from each cavity of the disc at a transfer station, and a connecting duct through which the portion of tobacco ejected by the push rod from each cavity passes directly to a wrapping station where the pouches are formed, filled with the tobacco product and sealed. The sealing may be performed using ultrasonic welders.
US 2008/029116 A1 relates to a smokeless tobacco product comprising a water-permeable pouch containing a tobacco formulation and an outer packaging material enveloping said pouch and being sealed so as to allow a controlled environment to be maintained within. An exemplary granulated tobacco formulation is disclosed to contain about 15 to about 30 parts mannitol powder and to have a moisture content of about 4 percent (see Example 2).
During manufacturing of some oral pouched snuff products, in particular during high-speed manufacturing, undesirable discoloration, such as slightly yellowish, brownish and/or dark spots, has been found on some products. These discolored pouched snuff products are usually disqualified for distribution to consumers. Thus, there is a need for a method for producing oral pouched snuff products which provides for reduced waste during pouch formation (i.e. during portion-packaging of snuff composition).